本文主要探討在垂直差異化的雙佔市場下，若廠商使用誤導性廣告並透過廣告代言人效果使消費者對產品品質產生誤解時，社會福利將如何變動。另外同時分析廣告代言人收取額外費用以及政府實行最低品質標準時，廠商行為的改變如何影響社會福利。我們發現當廠商的廣告水準提升時，一般來說將會造成社會福利的損失，而廣告代言人收取額外費用會間接增進社會福利。最後若政府進行最低品質標準管制時，只有在消費者對高、低品質產品主觀品質的感受差異足夠大的情況下才會改善社會福利。

In a duopoly model with vertical differentiation, the firms want to mislead the consumer’s awareness of the product quality by the effect that advertising endorser manufacturing, and this paper mainly discusses such this misleading advertising how to impacts social welfare. We also analyze when the advertising endorser charges an extra fee or government implements the minimum quality standards, what will happen on the firm’s behavior. We find that when the firm increases the level of advertising, social welfare will lose generally. The advertising endorser charges an extra fee will lead to an improvement on social welfare indirectly. And if government implements the minimum quality standards, only when the consumer’s awareness of the quality between high quality and low quality is large enough that will improve social welfare.

謝辭 ii
摘要 iii
Abstract iv
目錄 v
表目錄 vi
第一章 緒論 1
第一節 研究動機與目的 1
第二節 研究方法與架構 2
第二章 文獻回顧 4
第三章 理論模型 7
第一節 模型假設 7
第二節 均衡分析 9
第四章 福利分析 12
第一節 政府未管制下之社會福利 12
第二節 代言人參數分析 16
第三節 政府管制下之社會福利 19
第五章 結論與建議 23
第一節 結論 23
第二節 未來研究建議與方向 24
參考文獻 25
附錄 27

一、 中文部分
1. 陳玉晏(2015)，「產品品質管制政策分析」，國立中央大學產業經濟研究所博士論文。
2. 簡志憲(2006)，「廣告效果與產品品質」，國立中正大學國際經濟研究所碩士論文。

二、 英文部分
1. Bloch, F. and Manceau, D. (1999). “Persuasive advertising in Hotelling's model of product differentiation.” International Journal of Industrial Organization, 17, pp.557-574.
2. Von der Fehr, NHM. and Stevik, K. (1998), “Persuasive Advertising and Product Differentiation.” Southern Economic Journal, 65, pp.113-126.
3. Grossman, GM. and Shapiro, C. (1984). “Informative advertising with differentiated products.” Review of Economic Studies, 51, pp.63-81.
4. Hattori, K and Higashida, K. (2012). “Misleading advertising in duopoly.” Canadian Journal of Economics, 45, pp.1154-1187.
5. Hamilton, SF. (2009). “Informative advertising in differentiated oligopoly markets.” International Journal of Industrial Organization, 27, pp.60-69.
6. LeBlanc, G. (1998). “Informative advertising competition.” The Journal of Industrial Economics, 46, pp.63-77.
7. Moraga-González, J.L. (2000). “Quality uncertainty and informative advertising.” International Journal of Industrial Organization, 18, pp.615-640.
8. Motta, M. (1993). “Endogenous quality choice: price vs. quantity competition.” The Journal of Industrial Economics, 41, pp.113-131.
9. Nelson, P. (1974). “Advertising as Information. ”Journal of Political Economy, 82, pp.729-754.
10. Schmalensee, R. (1978). “A model of advertising and product quality. ”Journal of Political Economy, 86, pp.485-503.
11. Valletti, TM. (2000). “Minimum quality standards under Cournot competition.” Journal of Regulatory Economics, 18, pp.235-245.